The invention concerns a diffusor with at least one wall which surrounds an inlet round cross-section that, across the height of the wall of the diffusor, passes into an angular cross-section at the outlet of the diffusor. The invention further concerns a ventilator with an impeller and a diffusor that is in particular embodied as described above. The invention further concerns a device with such ventilators.
FIG. 12 shows a freestanding device according to the prior art (DE 35 15 441) that is provided with a housing. On its topside, ventilators, mounted on heat exchangers, are provided. The ventilators blow out air unhindered so that the entire dynamic energy is lost at the ventilator exit.
In order to reduce the considerable flow losses at the exit of pipe conduits, ventilators and the like, exit diffusors are used (DE 20 2011 004 708 U1, FR 27 28 028). On devices, for example, tabletop coolers, there is however only a limited space available in radial direction. Since the exit diffusors have a circular cross-section, the ventilators with the exit diffusors cannot be arranged tightly adjacent to each other. This is however often required for such devices where the ventilators must be arranged also in multiple rows tightly adjacent to each other. Therefore, a lot of space is lost on a device with several ventilators. Thus, local dead water zones which lead to increasing losses are also formed between the diffusors.
The invention has the object to design the diffusor of the aforementioned kind as well as the ventilator of the aforementioned kind such that the space on the devices can be optimally utilized without a constructively complex configuration being required for this purpose.